Either way, I understand why you’d want to delay your announcement as long as possible. But it’s already mid-March. Waiting this long might be working for you, but it isn’t good for the city you adore.

Look, I get how difficult this is. You love being mayor more than anyone ever loved anything. The job you once never dreamed you’d have is now the only one you can imagine doing. And you’ve been very good at it.

Nothing you could do after this would come close to the genuine delight you take in those community meetings and neighborhood parades. Nothing could compare with the power you have now, the near-universal obeisance you enjoy from East Boston to West Roxbury. Where would you go from here? You’re not like other guys. Academia isn’t your bag. Cushy ceremonial posts would bore you silly. You’re not the corporate type.

It’s hard to let go.

But if you are going to let go, Mr. Mayor, I implore you to do it soon.

Because the city deserves a real campaign to decide who should succeed you. It deserves a full discussion — not a hasty one — of how far Boston has come, and of where it should be headed. It deserves the best possible candidates vying to lead us forward. And right now, only one guy who could make a credible run has been brave enough to say he wants the job.

I like City Councilor John Connolly, but I’d also like a real race here. Every day you wait to say you’re out makes that less likely. All over the city, other aspiring mayors are sitting on their hands, just like they do every cycle. They’ll run only if you don’t. They’re doing this not just because they respect you, but because they fear you: You’ve made sure anybody who dared to challenge you became a social and political pariah. Running against you is a professional suicide mission.

If you announce you’re done, the mad dash to the mayoralty will begin even before you’ve stepped away from the podium. The thing is, anyone hoping to make a credible run for the job should have started raising money long ago. They should have begun building name recognition and campaign operations. For some potentially great candidates, it’s already too late.

But maybe you’re not going to let go, Mr. Mayor. Maybe you reckon that, in spite of your health problems, you still have it in you to lead this city. You need to tell us that now, too.

I know waiting makes sense politically. If you’re an incumbent, a short race is a good one, especially when half the city has met you personally. But here again, what works for you isn’t best for Boston.

We’re at a critical moment here. In some ways, the city has transformed on your watch: Most neighborhoods are vibrant and pretty, the Seaport has come alive, some schools are stellar. But Boston remains a deeply segregated place, with woefully uneven access to good education, affordable housing, safety.

If you run, you’ll be looking to add an unprecedented sixth term to your unprecedented fifth. Shouldn’t we have a proper vetting of your plans for the future, and of your capacity to carry them out? For that, we need a substantive campaign, not a sprint.

Maybe voters will conclude you’re still the best guy for the job. Fine. But they should be able to decide that on the merits, and not because you waited so long to announce that there was little time for a real discussion of your tenure.